Reversible engine control equipment



Patented June 17, 1952 REVERSIBLE ENGINE CONTROL EQUIIMENT Ralph .T. Whitney, Irwin, Pa., assignor to Westinghouse Air Brake Company, a corporation of Pennsylvania Application June 18, 1949, Serial No. 100,069

12 Claims. 1

This invention relates to reversible engine control equipment and more particularly to control apparatus adjustable in accordance with direction of rotation of a reversible engine.

In certain fluid pressure control systems for controlling the reversing of a reversible internal combustion engine, a, direction sensing interlock valve device is employed to eiect holding of the fuel supply to the engine cut-off until the engine is rotating in its proper direction in accord with dictates from an operators control device. Such an interlock device usually comprises a retractable shoe which is adapted to be brought into frictiona1 contact with a rotatable part such as the engine crank shaft when in rotation to be biased in one direction or another according to directionof such rotation by a force generated by the frictional contact.

Heretofore in the control systems employing the above direction sensing interlock device, during reversing of the engine, the retractable shoe was brought into frictional contact with the engine crank shaft when same was, rotating at relatively high speed and held in such contact until the engine was turning over in its reverse direction at relatively high speed: Such frictional contact of the retractable shoe with the rotating shaft resulted in unnecessary wear of the shoe and crank shaft. It is, therefore, a prime object of the present invention to provide an improved engine control apparatus employing a direction sensing interlock device in which wear of the retractable shoe will be minimized.

Other objects and advantages will become apparent from the following more detailed description of the invention.

In the accompanying drawing; Fig. 1 is a schematic view, partly in outline and partly in section, of one embodiment of the invention; Figs. 2, 3 are schematic views of portions of alternate embodiments of the invention; Fig. 4 is a detailed cross-sectional view of an inverse double check valve device employed in the structure shown in Fig. 2; and Fig. 5 is a detailed schematic crosssectional view of a relay valve device one or several of which is or are employed in each of. the embodiments shown in Figs. 1, 2 and 3.

DESCRIPTION OF FIG. 1

The reversible engine(not shown) may comprise the usual crank shaft I, only a portion of which is shown in cross-section in the drawing, a cam shaft 2, only a portion of which is shown in outline in the drawing, and iuc1 control shaft 3. A

The engine crank shaft l may be operably connected to the pistons (not shown) of the engine and operatively connected to means to be driven (not shown) such as a propeller or propellers on a ship, for example.

The engine cam shaft 2 is adapted to be driven in proper phase with the crank shaft l in the usual manner for operating conventional engine valve mechanism (not shown) to permit the engine to be started by means (not shown) for operation on fuel in either direction of rotation, to, for instance drive a ship ahead or astern. The cam shaft 2 may have the usual forward cams (not shown) to provide for operation in one or an ahead direction and the usual reverse cams (not shown) to provide for operation in the reverse or astern direction. In the wellknown manner, the cam shaft 2 may be shifted axially in one direction to one position for rendering the forward cams effective to operate the engine valve or timing gear, and in the opposite direction to an opposite position for rendering the reverse cams effective to operate said gear.

The fuel control shaft 3 is operatively connected to fuel control valve means (not shown) for efiecting regulation of the quantity of fuel supplied to the engine cylinders by way of fuel injection nozzles or the like (not shown). The control shaft 3 is secured for turning movement by such as a fuel control lever 4, which is adapted to be moved to a Fuel off position, indicated by a dot-and-dash line so titled in the drawing, in which position the fuel control valve means is so conditioned as to cut off supply of fuel to the engine cylinders, as is necessary to reverse the engine for example.

The control apparatus embodying the invention comprises a cam shift cylinder device 5 for eiecting shift of the engine cam shaft 2 to condition the engine for operation in one direction or the other, a fuel cut-off cylinder device 6 for effecting movement of the fuel control 1ever 4 to its Fuel ofif position as in stopping or reversing the engine, an operators control device 1 for controlling operation of the cam shift cylinder device 5 in reversing the engine and the fuel cut-off cylinder device 6 in stopping the engine. directional interlock device 8 operable to sense the direction of rotation of the engine to control operation of the fuel cut-off cylinder device 5 in reversing the engine, a relay valve device 9 operable to render the fuel cut-oi cylinder device responsive to either the directional interlock device 8, as in reversing the engine, or to the operators control device l as in stopping the engine, and a double check valve device o arranged in cooperation with certain control pipes to be described subsequently for controlling operation of the relay valve device 9.

The cam shift cylinder device is shown in longitudinal section in Fig. 2 and for sake of illustration, may simply comprise a hollow cylindrical casing [5 having a cam shift piston l5 sliclably disposed therein which is exposed on its one face to a chamber Il and on its opposite face to a chamber 8. Fluid under pressure may be conveyed to and from the chamber ll by way, of such as an ahead control pipe I9 and to and.

from the chamber IB by way of such as an astern control pipe 2:3. In response to supply of fiuid under pressure to the chamber H by way of the ahead control pipe 9, while the chamberl8is vented va the astern control pipe 20, the cam shift piston l'i will be caused to move in one di-.

rection tothe position in which it is shown in Fig. 2, which maybe called its.fAhead position, so titled in the drawing, Conversely, in response to supply of fluid under pressure to the chamber l8 by way of the astern.control pipe 20, while thechamber ll is vented by way of the ahead control pipe l9, the piston H5 will be caused to move in the opposite direction to a position opposite to that in which it is shown in Fig. 2, which position may be called its l Astern position indicated in the drawing by a dot-and-dash line so titled. The cam shift piston IS is operatively connected to the engine cam shaft 2 through the medium of a rod which extends outwardly in an accommodating opening in the end wall of thecasing l5. When the cam shift piston l5is caused to assume its Ahead position, the engine cam shat 2 will be caused to assume its corresponding position to condition the enginefor operation in its forward or ahead direction, and when the cam shift piston is caused to assume its Astern position, the engine cam shaft 2 is caused to assume its corresponding position to condition the engine for operation in its reverse or asterndirection.

The fuel cut-off cylinder device 6, forsakeof illustration, may comprise a hollow cylindrical casing havinga fuel cut-off piston 31 slidably disposed therein. Piston 3l -is exposed at its one face to a pressure chamber 32 and at its opposite face toa spring chamber 33 which latter chamber is constantly open to atmosphere. A stop rod 34, attached to piston 35, extends outwardly through an accommodating opening in one end wall of the casing30-for engagement with the fuel control lever 4. When fiuid under pressure is supplied to the pressure chamber 32, the piston 3| will be caused to assume such as the position in which it is shown in the drawing,

with the stop rod 34 in engagement with the fuel control lever 4 and holding same in its Fuel oi position. Upon release of fluid under pressurefrom the pressure chamber 32, the piston 3| Will be moved in the direction of said chamber 32 by a compression spring 35 in chamber 33 to a position defined by contact with such as a shoulder 36 in which position of saidpiston the stop rod 34 will be retracted away from the fuel control lever 4 to allow same to be moved in the direction of a Fullfuel position by means of suchas a speed governor device (not shown) for effecting supply of fuel to the engine.

The operators-control device l may be.substantially like thatshown and described in detail in United States Patent No. 2,413,390 issued to Roy R. Stevens, December 31, 1946, and assigned to the assignee of the present application. For a detailed description of such a device l, reference may be made to the above patent.

Briefiy, the operators valve device l comprises valve means (not shown) for controlling supply of fiuid under pressure from such as a reservoir 4l by way of a control supply pipe 40 selectively to the ahead control pipe IS, the astern control pipe 20 and to a start control pipe 42 and release of fiuid under pressure therefrom as :well as for effecting variation in pressure of flu.id in a speed control pipe 43. An operators controllever 44 'is provided for controlling operation of-.the valvemeans comprised in the device l.

The operators control device disclosed in the above mentioned patent is employed in systems for controlling the starting, stopping, running, reversing,,.etc. of a reversible engine, but since the'function and operation of the invention does not involve the useoft more than the ahead and astern control pipes I9 and 2D, only those positions of theoperators control lever 44 of device 1 for controlling selective establishment of pressure in said.pipes .l9 and 20 will be described in the present application.

In operation,0f the control valve device l, the operatorslever 44 is movable to a Stop position in which it is shown. in the drawing and in whichposition both. the ahead and astern control .pipesare-vented teatmosphere. The 0perators control lever 44 may be moved out of its Stop? position in..one.directon indicated in the drawing by an arrow and a legend Ahead to effect supplyof fiuid under pressure from the control supply pipe 40 to the.ahead.control pipe IB while maintaining the astern control pipe 26 vented to: atmosphere The operators control lever-44 may. also be moved out of its Stop position inthe opposite direction indicated in the drawing .by an arrowand a legend Astern to efiect supply of fluid under pressure frompipe 40 to the astern.control pipe 20 while the ahead control pipe 19 is maintained vented to atmosphere. The return of the operators control lever 44 to Stop position from either Ahead or Astern will effect simultaneous venting of both the ahead and astern: control pipes l9 and ,20. In reversing the engine, the operators control lever 44 may be moved froma position on. whichever side of Stop position it may,bein to a position on the opposite side of Stop. positionwithout pause in said Stopposition toeiect a reversal in pressure conditions in the ahead and astern control pipes l9 and 20; For example, the control lever 44 may bemoved continuously from a position on-theAhead sideof Stop position to a position on the Astern side of Stop positionthereby effecting venting of the previously charged ahead control pipe l9 and pressurization of the previouslyvented asterncontrol pipe 29, the effecton pressureconditions in pipes 19 and 2of moving handle 44-through Stop position during the above movement may be neglected due to the fact that the'lever 44-will occupy Stop position only momentarily in passing through.

The directional interlock device 8 in the usual form comprises a casing having two poppet valvesl3l and l32 contained in chambers 33 and l34 respectively; The poppet valves l3l and 32 are arranged side by side with parallel extending fluted stems and [36, respectively, which extend into a delivery chamber l31 common to both. The valves l3l and 132 are provided to control communication between the chambers 133 and 34, respectively, and the chamber E31. A spring [33 in each of the chambers 133 and 134 acts on the respective valve l3l, E32 to urge same toward a closed position, in which position the valve 3| is shown in the drawing,

The valve stems 3.5 and [3B engage, respectively, two spaced apart operating plungers 139 and ME) which are slidably mounted in the casing and which are provided with stems Mi and M2 extending outwardly through the casing. Two rockable cams M4 and M5, fulcrumed on pins secured to the casing, are provided for actuating the plungers MI and [42, respectively. These cams may be identical but reversely arranged, and each is operatively connected to the respective plunger Ml, M2 through the medium of a follower element M: rockably mounted on a pin secured in the casing. Each of the cams M i and M5 is provided with a surface M9 which, when in engagement with the respective element [41, will unseat the respective valve l3i or 32. Adjacent to the surface M9, each cam is provided with a recess 5B which is adapted to receive the respective element l l! to permit movement of the respective plunger 39 or MB by a respective spring I5I to a position to permit closure of the respective valve 3| or 32 by the respective spring [33.

The two cams 44 and M5 are operatively connected for movement in unison by a link 52, and since the cams are reversed as above mentioned, movement of the link and cams to the position in which they are shown in the drawing will effect opening of the valve 32 and closure of the valve l3l, while movement of said link and cams in a clockwise direction, as viewed in the drawing, to a position in which the surface M9 on the cam Hi4 engages the respective element Mi will effect opening of the valve l3l and Closing of the valve 32.

The directional interlock device 8 further com prises a shoe actuating piston !54 which is op" eratively connected to the link l52 by means of a piston rod 55, which extends through a nonpressure chamber l5ii at one side of said piston. At the opposite side of the piston E54 there is a piston or pressure chamber 151.

by a pin [59 With a friction shoe lti which is adapted and arranged for frictional engagement with the outer surface of the crank shaft l. The

piston rod 55 is also operatively connected by means of pin Hi3 to one end of a link Hi3, the opposite end of which is operatively connected to the link 652 by means of a pin [63.

The piston rod 55 is capable of side movement in the non-pressure chamber G56 from the position in which it is shown in the drawing, and which is defined by contact with a surface M in the casing, to a position in which said rod engages a surface [65 in the casing. Adjacent to the surface Hi5, the casing is provided with a pin N35 which is arranged to engage in one of two recesses lii'l, Hi8 according to whether or not the piston rod is in the position in which it is shown in the drawing or is in its opposite position engaging the surface l65.

When fluid under pressure is supplied to the pressure chamber l 5!, in a manner which will be described herein subsequently, the piston l5@ will move the friction shoe IBI into engagement with the engine crank shaft l which, if rotating,

The opposite or outer end of the piston rod E55 is connected 6.. will bias the rod 155 toward one or the other of surfaces [64 or 65, according to the direction in which said shaft is turning. At the time of engagement of the shoe ISI with the shaft I, the link [63 will be disposed away from the pin 56, so that the rod is free for sidewise movement to effect positioning of the cams 144 and M5 accordingly. If, at the time of engagement of the shoe l 5| with the shaft l said shaft is rotating in its forward or ahead direction, the rod 55 will be biased to the position in which it is shown in the drawing in leaning engagement with the surface 64, and the cams IM and M5 therefore will be caused to assume the positions in which they also are shown in the drawing with the valve El consequently closed and the valve 32 open. If, conversely, the shaft l is rotating in the reverse or -astern direction at the time of engagement by the shoe 61, the rod l55 will be caused to assume its opposite position in leaning engagement with the surface [55, thereby effecting shift of the cams [44, 145 to their positions in which the valve 32 is closed and the valve l3l is opened. If, however, at the time that the shoe IBI engages the shaft I, said shaft is static, the rod l55 will remain in leaning engagement with whichever of the shoulders 64 or 65 it may be in such engagement with at the time. Upon release of fluid under pressure from the chamber 51, a spring ll0 will move same in the direction of said chamber to a rest position in which it is shown in the drawing, while the shoe IBI will thereby be moved to a corresponding rest position seated on accommodating shoulders I'll formed in the casing. The link 63 will return into contact with the pin IESS which will project into one or the other of the recesses !S'l or 63 to lock the piston rod 155, cams [44, M5, and the valves I3l, 32 in the positions which they were caused to assume when the shoe lfil last engaged the shaft when rotating.

Referring to Fig. 5, for sake of illustration, schematically the relay valve device 9 shown in outline in Fig. 1 may comprise a casing 23! having a diaphragm 2ill disposed therein subject to pressure of fiuid in a diaphragm control chamber 282 at its one side and to atmospheric pres sure in a chamber 253 at its opposite side. Also formed in the casing are chambers 2M, 285 and 236, chamber 204 being sepaarted from the chamber 203 by a partition 2)? and from the chamber 295 by a partition 298. A partition Zi. separates the chamber 25 from the chamber 235. A valve 2M] is disposed in the chamber 204 for controlling communication between the chamber 235 and said chamber 2134. The valve 2 may be secured to a fluted stem 2 l l slidaoly mounted in a suitable bore extending through the partition 293, a valve seat being formed at the end of the bore that opens into the chamber 204 for accommodating the valve 23. A valve 2l2, similar to the valve 2 ID, is disposed in the chamber 205 for controliing communication between the chamber 265 and said chamber 205. The valve 2 E2 is attached to a fluted stem 213 which is slidahly disposed in a suitable bore extending through the partition 259, a valve seat being formed in the end of said bere opening into the chamber 206 to accommodate the valve 2!2. Both of the fluted stems 2 H and 2l3 project into and meet in the chamber 235. A bias spring 2M is disposed in the chamber 2535 arranged to urge the valve 2fl2 towards lts seat,

and at the same time, through engagement of stems 2H and 2l3, to urge the valve 2iil away from its seat. The valve 2Hi is operably con 79 nected:to the diaphragm .20l' by ineans of a rod or stem 2| 5 which extends through a bore in the partition 201. A control spring 216 is provided in the chamber 203 to oppose deflection of the diaphragm 201 in the direction of the chamber 203.

In operation of the relay valve device shown in section inv Fig. 5, with the chamber 203 constantly open to atmosphere by way of such as a casing port-203", upon supply of fiuid under pressure to the control chamber 202, the diaphragm 201 will defiectin the direction of the chamber 203 against opp0sition of the control spring 2I5 and the bias spring 2 l l and will cause seating of thevalve 2I0 and unseating of the valve 2|2. With the valve 2 l0 closed and the valve 2 l2 open, the chamber 205 will be*cl0sed to the chamber 204 andopen to the=chamber 206. Upon subsequent Venting;offluid under pressure from the control chamber 202; the bias spring 2M and the control spring 2I6-will return the diaphragm 20| and valvs 2|0 and2 l2 to the positions in which they are shown in the drawing; the valve 2 2 being; seated' and the valve 2 l0 being unseated. Withthe valve2l0 unseated and the valve 2.l2 seated, the chamber 205 will be closed to the chamber 206and open to the chamber 204.

Hereinafter; in descr'ibing operation of the relay valve device 9 shownin outline in Fig. 1, as well, as those to be described hereinafter and showninligs. 2 and 3, when the control chamber is vented to atmosphere and the valves 210 and 2 l2 are consequently unseated and seated, respectively, resultant connection between the chamber 205 and the chamber 204 by way of the unseated valve 2 l0 will bereferred to as a communication ll8 which is represented symbolically in the drawing in each instance by a solid line appearing within the outline of the relay valve device. Similarly, when the valve 2l0 is seated and the valve 2l2 is unseated as a consequence of supply of fiuid under pressure to the control chamber 202 in the relayvalve device, the resultant connection between the chamber 205 and the chamber 206 by way of the unseated valve 2 I2 will be re.ferred to as a communication H9, indicated symbolically in the drawing by a dash line appearing within the general outline of the device.

The double check valve device 10 shown in outline in Fig. 1 may be of any well-known structure and for sake of illustration may simply comprise a casing having a piston valve (not shown) slidably mounted therein to control communication between one or the other of two opposite like inlet openings and an outlet opening.

In operation of the double check valve device lil, when fluid under pressure is supplied to one of its inlet openin'gs with the other of said inlet openings vented, the piston valve will be caused to assume a position which closes oii from the outlet opening whichever of said inlet openings is vented and opens to said outlet opening whichever of said inlet openings is pressurized. Upon venting of both inlet openings to atmosphere, the outlet opening will vent to atmosphere va one or the other of said-inlet openings depending upon the position of the piston valve at the time.

In the relay valve device 9, its control chamber 202 isconnected tothe outlet opening of the double check valve device lo by way of a pipe 300, its chamber 204 is connected to a branch of the control supply pipe Mi, its chamber 205 is connected to the pressure chamber 32 in the fuel cut-off cylinder device6 by Way of such as a pipe 30l, anditschamber 206'isconnected to the delivery chamber 131 in the directional interlock device 8by way of such as a delivery pipe 302.

In the double check valve device 0, its outlet opening is connected to the pipe 300 as aforementioned, and'its inlet openings are connected to the ahead and astern control pipes I 9 and 20 respectively.

According to a feature of the invention, the pressure chamber 151 in the directional interlock device 8 is connected to the delivery chamber 31 therein by way of conduits or pipes 305 and 305 connected respectively to chambers 31, l5'l and to each other to allow for automatic release of fiuid under pressure from the chamber 151 upon rotation of the engine crank shaft in accord with dictates of the operators control device l, as will'be described in detail subsequently.

OperationFig; 1

Assume now that the operators lever 44 of the operators control device 7 is in its Stop position, with both the ahead and astern control pipes 9 and 20 consequently vented to atmosphere, The pipe 300, hence the control chamber 202 in the relay valve device 9, will be vented to atmosphere by way of the double check valve device ifl' and one or the other of the now vented control pipes 29 and 20. With its control chamber thus vented to atmosphere, the relay valve device 9 will be positioned with its communication il3 established, connecting the pipe 3l. to the control supply pipe ail so that the chamber 32 in the fuel cut-oil cylinder device 5 will be charged with uid under pressure. The fuel cut-off piston 35 consequently will be in the position in which it is shown in the drawing, with the stop rod 3 i holding the fuel control lever 4.in its Fuel ofi' position to prevent supply of fuel.to the engine at this time.

Assume further that the engine was last operating in its forward, or ahead, direction. The cam shift piston IS in the cam shift cylinder device 5 will be in its Ahead position in which it is shown in the drawing with the engine cam shaft 2 also correspondingly positioned to condition the engine for. operation in its forward direction. Both of the chambers H and 18 in the cam shift cylinder device 5 will be vented to atmosphere at this time by way of the now vented ahead and astern control pipes 9, 20 so that the cam shift piston H3 and engine cam shaft 2 will remain static.

After previous operation of the engine in its ahead direction, the directional interlock device 8 will be in the position in which it is shown in the drawing, with the valve 132 open, and the valve [3| closed. Its delivery chamber l3'i thereforewill be disoonnected from the ahead control pipe l9 and connecte to the now vented astern control pipe 20 by way of the unseated valve [32. The pressure chamber 51 in the directional interlock device 8, being connected to the chamber E37, therefore will be vented at this time by way of the astern control pipe 2. With pressure chamber I51 vented, the piston 54 will be in its rest position in which it is shown in the drawing with the friction shoe [El consequently in a retracted rest position seated on shoulders lll and disposed away from the now static engine crank shaft Since when the shoe l EH was last in engagement with the engine crank shaft l said shaft was turning in its ahead direction as assumed, the piston rod will be locked by pin i6 6 in notch E63 in the position in which it is shown in the drawing in leaning engagement with the surface 64, thereby holding, through respective position of the cams l44, 45, the valve 132 unseated and allowing the valve l3l to be in its seated position by virtue of the force of the respective compression spring 38.

Now assume that, as in the usual manner, that the operators lever 44 is moved out of Stop position in the Ahead direction to effect starting of the engine in its ahead direction by means (not shown). In response to this movement of the operators lever 44, supply of fluid under pressure to the ahead control pipe l9 will be effected by the device 1. Fluid under pressure from the ahead control pipe l9 will flow into the chamber ll in the cam shift cylinder device 5, but since the cam shift piston !6 is already in its Ahead position at the time, said piston will remain static with the engine cam shaft 2 remaining in its corresponding position conditioning the engine for operation in its ahead direction. From the ahead control pipe 9, fluid under pressure will also flow to the control chamber 202 in the relay valve device 9 to cause same to disestablish its communication ll8 which connects the pipe 3Ill to the control supply pipe 40 and to establish its communication H9 which connects said pipe 301 to the pipe 302 thence to the chamber [31 in the directional nterlock device -8. Since, as afrementioned, the directional inteflock device 8 is in its ahead position at this time with its valve l3l closed and its valve 132 open, fluid under pressure will release from the chamber 32 in the fuel cut-off cylinder device 6 by way of the pipe 30l, the newly established communication H9 inthe relay valve device 9, the pipe 302, chamber I3'l in the directional interlock device 8, the unseated valve 132 and chamber [34 therein, and the astern control pipe 20. The fuel cut-off piston 3| will then be caused to assume its release position in which the stop rod 34 is disposed away from the fuel control lever 4 to allow the fuel control shaft 3 to be positioned to effect supply of fuel to the engine.

Fluid under pressure supplied to the ahead control pipe l9 will also flow into the chamber 33 in the directional interlock device 8, but such fluid under pressure will not reach its chamber 931 since its valve I3l is seated.

It should be pointed out that during the time that the above is occurring, the pressure chamber 51 in the directional interlock device 8 remains vented by way of the pipe 305, the pipe 305, and the chamber l31 so that the friction sh0e will remain in its rest position disposed away from the engine crank shaft l.

It will be seen from the foregoing description that when the operators lever 44 is moved out of Stop position to effect starting of the engine in the same direction in which it last operated, the fuel cutoff cylinder device 6 is released, while the piston 154 in. the directional interlock device B remains in its rest position, thereby conserving fluid under pressure over former systems employing such a device in a manner which caused operation of the piston 54 and engagement of shoe IBI with shaft,l when starting the engine in the same direction in which it last operated. In addition to conservation of fluid under pressure, in employing the directional interlock device 8 in fashion as illustrated in the present application, what is even more important, the wear. on the shoe- IBI is greatly reduced over the previous methods of employunder pressure will then release from the chamber H in the cam shift cylinder device 5, directly by way of the ahead control pipe [9, and from the control chamber 202 in the relay valve device 9 by way of the pipe 300, double check valve device e and the now vented ahead control pipe.

Upon the above venting of fluid under pressure from the chamber I'l in the cam shift cylinder device 5, the cam shift piston B and hence the engine cam shaft 2 Will remain static in position to condition the engine for operation in its ahead direction.

Venting of fluid under pressure from the control chamber 2l32 in the relay valve device 9, however, renders said device responsive to disestablish its communication H9 which connects the pipe 3B! to the pipe 302 and to establish its communication H8 which connects said pipe 3ll to the control supply pipe 40, whereupon fluid under pressure will flow thereby to the chamber 32 in the fuel cut-oif cylinder device 6 to cause the stop rod 34 to assume the position in Which it is shown in the drawing, moving the fuel control lever 4 to its Fuel off position to terminate supply of fuel to the engine for stopping same from operation in its ahead direction. All parts of the apparatus will now assume the positions in which they were described previously with the engine stopped subsequent to its operation in the ahead direction.

Now assume that, with the engine stopped after previous operation in its ahead direction and With the operators control lever 44 in its Stop position, it is desired to efiect starting of the engine in a direction opposite to that in which it last operated, in its astern direction for example. The operators lever 44 will be moved out of its Stop position in the direction of Astern to effect supply of fluid under pressure to the astern control pipe 28 while maintaining the ahead control pipe l9 vented as in Stop position.

Fluid under pressure thus supplied to the astern control pipe 2il will flow to the chamber I8 in the cam shift cylinder device 5 and to the chamber l5l' in the directional interlock device 8 by way of chamber 34, unseated valve l32, delivery chamber l31 and the pipe 305, 305 therein, and

- to the control chamber 202 in the relay valve device 9 by way of the double check valve device lil and the pipe 308.

In response to supply of fluid under pressure to chamber l8 in cylinder device 5, with its chamber l vented va the astern control pipe 20, the cam shift piston [6 will 'be caused to assume its Astern position opposite to that in which it is shown in the drawing to shift the engine cam shaft 2 to its corresponding position to condition the engine for operation in its astern direction.

In response to fluid under pressure supplied as above to its control chamber 2il2, the relay valve device 9 will respond to disestablish its communicahtion HS which connects the pipe 30l to the control supply pipe 49 and to establish its communication H9 which connects the now charged delivery chamber l3'l in the directional interlock device 8 to the pressure chamber 32 in the 1 1 fuel cut-off cylinder device 6, va pipes'30l and 302, so that at this time the fuel control lever 4 will be held in its Fuel off'position by effect of pressure of fluid held in the chamber 32.

Pressure of fluid'suppled to the delivery cham- 'ber 131 in the directional interlock device 8 from the now charged astern control pipe 20 will also flow va pipe and passage 305 to the pressure chamber l'l therein. In response to supply of fiuid under pressure to the Chamber [51, the piston 54 will be caused to move the friction shoe i6l into engagement with the engine crank shaft l which may yet be static at the time. With the friction shoe IBI in engagement with the engine crank shaft l, when the engine is caused to turn over in its astern direction, said shoe in being biased to follow movement of the crank shaft will cause, through shift in position of link 152 and cams l44, [45, s'eating of the valve l32 and unseating of the valve l3l, whereupon fluid under pressure will release from the pressure chamber 32 in the fuel cut-off cylinder device 6 by way of pipe 30 I Communication I a in relay valve device 9, pipe 302, chamber 131 in directional interlock device 8, the unseated valve l3l and the ahead control pipe IS to allow stop rod 34 to be retracted from the fuel control lever 4 to allow the fuel control shaft 3 to be moved to effect supply of fuel to the engine. Also, upon closure of the valve I32 and opening of the valve i3l in the directional interlock device 8, fluid under pressurein the chamber l51 therein will release to atmosphere by way of the pipe 305, the pipe 305, the chamber I3I, the uhseated valve l3l, chamber l33, and the vented astern control pipe 20. Upon release of fluid under pressure from the pressure chamber 51, the piston 154 will be caused by action of the spring l'l to return to its rest position, with rod l55 in leaning engagement with surface 65 and the link l52 locked in position by pin 166 in the b notch IG! to hold the cams [44, l45 so positioned as to hold the valve I3I unseated with the valve I32 seated.

It will be seen that when the engine is started in a direction opposite to that in Which it was last operated, astern after operation'ahead, for example, as above described, according to a feature of the invention, With the friction shoe IBI held in contact with the engine crank shaft l by pressure of fiuid in the pressure chamber l51, by G virtue of the connection 305 with the chamber 31, as soon as the shaft l is started to turn in its new, or astern, in the present instance, direction, fluid under pressure in said pressure chamber 151 is automatically released by way of said chamber I 31 to allow spring I to move the friction shoe I6l to its retracted position away from the rotating shaft I. It will be appreciated that such retraction of shoe ltl will be affected automatically upon initial turning movement of the shaft l before same is actually rotating at any appreciable speed, therebypreventing unnecessary Wear on the shoethat otherwise occurs in previous arrangements employing a directional interlock device in such a fashion as allows the shoe to remain in engagerhent with the shaft for a considerable time after rotation in its new direction.

To stop the engine Operating in its astern direction, in the usual manner, the operators lever 44 is moved to whatever position it may be occupying at the Astern side of Stop position to the Stop position, thereby effecting venting of the astern control pipe along with the ahead control pipe IS already so vnted.

12 Fluid under pressurewill then release from the control chamber 202in the relay valve device 9 bywayof'the pipe3fl0 and"double check valve device lo to cause supply of fluid under pressure from the control supply pipe 40 to the chamber 32 in the fuel cut-off cylinder device 6 through establishment of the communication l I8 in said relay valve device. The "fuel cut-oi cylinder device position With shoe 'I6l 'r etracted and v'a1ves' I3l,

[32 open and closed, respectively.

It will be appreciated that in Operating the control apparatus to eifect starting of the engine ahead after previous operation astern, the directional interlock device 8 will respond in manner as aforedescribed, retiacting its shoe IBI upon initial turning-inovement of the shaft l in its new, or ahead direction before the shaft is yet turning at 'any appreciable speed.

Now assume that the engine is running --in-its ahead direction with th operators iver 44 positioned at the Aheadside of Stop""position and with the ahead control pipe le charged with fiuid under pressure and the astern control pipe 28 vented. As aforedescribed, the cam=shift'piston 16 "and" engine cam'shaft 2 willbeintheir' respectiv ahead positions, the relay valve device 9 will be pbsitioned with its communication H9 established, the directional interlock device 8 Willbe in its ahead position 'with the valve l 3l seated and the valve I32 unseated'so that'harnber" [31 will be connected to the vnted astern cotrolpipe 20. The chamber 151 in the directional interlock device 8 and the-chamber 32 in the fuel cut-Off cylinder device 6 will be vented to atmosphere by way of the chamber I3'l in said device 8. The friction shoe IBI in the directional interlocl device 8 therefore will be in its retracted'position away from the rotating engine crank shaft and the fuel cut-off cylinder device 6 will 'be in'its released position with the stop rod 34 disposed away from'the fuel control lever 4.

Now assme that in the usual manner, the opera'tors lever 44 is moved from its position on'the Ahead side of Stop*position directly toa position on the Astern sideof Stop position'for effecting a reversal in, the direction of operation of the engine from ahead to astern, for example. Venting of the ahead control pipe I 9 and charging of the astern control pipe20 is therebyeiected.

Venting the ahead control pipe l9 and charging the astern control pipe20 will not effect the status of the relay valve device 9, since itscontrol chamber 202 will remain pressurized when either-one or the other of the control pipes l9 or 20ispressurized by way of the double checkvalve device lo and: the pipe 300. The communication H9, therefore 'is' maintained established, connecting the chamber 32 in the fuel cut-'oi cylinder device 6 to the chamber I31 in the directional interlock device 8 by way 'ofthpipes 3M- ai1d32.

Fluid under pressure from the astern control unseated valve 1'32, into*the chamber l 3T in the directional interl0ck device-8, thence to the presvice 6 to cause cut-off of supply of fuel to the engine, as will be appreciated from previous description, and to the pressure chamber l'! in said device 8 to cause the friction shoe l6l to be brought into engagement with the crank shaft l rotating in its ahead direction. While the crank shaft continuas to turn in it ahead direction, the valves l3l, l32 in the directional interlock device S will remain closed and open, respectively, as will be appreciated from previous description.

At the same time, fluid under pressure supplied to the astern control pipe 20 will flow into the chamber [8 in the cam shift cylinder device 5 as fluid under pressure from the chamber l'l releases by way of the vented ahead control pipe I 9, so that the cam shift piston 18 will be caused to shift the engine cam shaft 2 from its ahead to its astern position to condition the engine for operation in its astern direction.

Upon completion of the above shift in position of the engine cam shaft 2, the starting means (not shown) may be brought into operation to oppose further rotation of the engine in its original or ahead direction and to turn the engine over in its new or astern direction.

Upon initial turning movement of the engine, hence crank shaft I, in the astern direction, the friction shoe [El in contact with said shaft will cause rocking of the rod [55 from its position in leaning engagement with the surface 164 to its opposite position in leaning engagement with the surface 65, causing through resultant movement of the link 152, rocking movement of the cams 44, M5 and threby unseating the valve l3l and allowing the respective spring l38 to seat the valve 32, as will be appreciated from previous description.

Upon closing of the valve 132 and opening of the valve I3l in the device 8 its chamber 31 will become vented to atmosphere va the unseated valve l3i and the now vented ahead control pipe i9 so that fluid under pressure will release from the pressure chamber 151 beneath piston 154 in device 8 to allow for retraction of friction shoe ISI to its rest position disposed away from the crank shaft l being brought into rotation, and

fluid under pressure will also simultaneously release from the pressure chamber 32 in the fuel cut-oif cylinder device 6 to allow for movement of the fuel control shaft 3 for effecting supply of fuel to the engine, as will be appreciated from previous description. It should be recalled that at the time that the chamber 31 in the directional interlock device 8 is vented va the ahead control pipe, the chamber 32 in the fuel cut-off cylinder device 5 is connected to said chamber I3'I by way of the pipe 301, communication IIS in the relay valve device 0, and the pipe 302.

It will be seen now that in efiecting reversal in direction of operation of the engine, the friction shoe 6| of the directional interlock device 8 is moved into frictional engagement with the engine crank shaft l while it is still turning in its original or ahead direction, and automatically retracted to its rest position disposed away from said shaft l substantially upon its initial turning movement in the new or astern direction, to prevent prolonged engagement of said shoe with the shaft when rotating in its new direction, thereby reducing the wear on said shoe.

Reversal in operation of the engine from astern to ahead may be eiected in similar fashion, with automatic retraction of the shoe 6| away from the shaft l upon its initial turning movement in its new direction.

14 Termination of operation of the engine in its astern direction will be eiected in fashion as aforedescribed, through movement of the operators control lever 44 from its position at the Astern side of Stop position to said Stop position.

DESCRIPIION OF FIG. 2

The structure shown in Fig. 2 comprises a relay valve device 400, which may be similar schematically to the relay valve device shown in detail in Fig. 5, and an inverse double check valve device 401 arranged to delay supply of fluid under pressure from the chamber I31 to the chamber I51 in the directional interlock device 8 during reversal of the engine until the engine cam shaft 2 has been shifted in order to reduce the length of time that the shoe IBI of device 8 remains in contact with the shaft l when rotating in its original direction, prior to automatic retraction of said shoe upon initial turning movement of said shaft in its new direction.

Referring to Fig. 2, in the relay valve device 400, its chamber 204 is connected to atmosphere by way of such as a pipe 350, its chamber 205 is connected to the pipe 305, hence to the pressure chamber 51 in the interlock device 8, and its chamber 206 is connected to the pipe 305, hence to the chamber 131 in said device 8.

In response to supply of fluid under pressure to its control chamber 202 by way of such as a pipe 32I, the relay valve device 400 will respond to establish its communication Il9 connecting the pipe 305 to the pipe 305 and thereby connecting the chambers El and 31 in the directional interlock device 8. In response to release of fluid under pressure from its control chamber 202, the relay valve device 400 will disestablish its communication ll9 and establish its communication H8 connecting the pipe 305, hence chamber 51 in device 8 to atmosphere via pipe 350.

Referring to Fig. 4, the inverse double check valve device 40l shown in outline in Fig. 2 may comprise a casing 323 having a bushing 324 which is encircled midway between its ends by an annular chamber 325 connected to the pipe 32 I. The bushing 324 is provided interiorly and midway between its ends with a bridge having an axial bore 326 open to chamber 325 through a plurality of radial openings 321. At one end of the bore 325 is an annular seat arranged for sealing engagement by a valve 320 contained in a chamber 329, while at the opposite end of said bore is an oppositely arranged annular seat provided for sealing engagement by a valve 338 contained in a chamber 33I. The two valves and 330 are connected for movement in unison by a stem 332 extending with clearance through the bore 326. This stem is of such construction as Will allow flow of fluid under pressure past either valve 328 or 330, when unseated, through the bore 326 to the annular chamber 325.

The chamber 33I is connected to a pipe 333 arranged to be connected to the chamber H3 in the cam shift cylinder device 5 just to the left of the cam shift piston l0 when said piston is in its Astern position opposite to that in which it is shown in the drawing. The chamber 329 in the inverse double check valve device 40l is connected to a pipe 334 arranged to be opened to the chamber |1 in the device 5 just to the right of the cam shift piston l6 when said piston is in its Ahead position in which it is shown in the drawing.

In operation of the inverse double check valve device '4lll, when only one of the pipes 333; 334 is Operaton-Fig. 2

In operation of the control system employing the structure shown in Fig. 1 modified as shown in Fig. 2, assume that the engine is stopped after previous operation in its ahead direction, for example. All parts of the apparatus shown in Fig.,

1 will be positioned as previously described and in which they are shown in the drawing with the operators control lever 44 in its Stop position. In Fig. 2, both pipes 333 and 334 connected to the inverse double check valve device 40! vented by way of the chamber H inthe cam shift cyiinder device 5 and the ahead control pipe 9 which is vented va the control device 1 in Fig. 1 at this time, as will be recalledfrom earlier description. With both the pipes 333, 334 thus,

vented as above, the pipe 321 and hence the control chamber in the relay valve device 433 will be vented by way of the inverse double check valve device 4|3l and the pipe 32 l, as will be appreciated from the previous description of operation of said, With its control chamber thus device 4l. vented, the relay valve*device 400 will be in its position in which its communication! l8 is established so that the chamber 151 in the interlock device 8 in Fig. 1 will be vented to atmosphere va the pipe 305 now connected to the pipe 350. The piston 54 and shoe l6l in the device 8will both be in their respective repose positions previously described.

Now assumethat the operators control lever -G4 in Fig. 1 is moved to a positionontthe Ahead side of Stop position to e1ect operation of the engine in the same, or ahead as assumed, direction in which it last operated. The ahead control pipe 9 becomes supplied with fluid under pressure as aforedescribed while the astern control pipe 23 remains vented. From the ahead control pipe, fluid under pressure will flow to the chamber 33 inthe directional interlock device 8, but is preventedfrom reaching the chamber l3'l therein by the seated valve I3l, and said chamber 131 will remain ventedby way of the unseated valvei 32 and the astern control pipe 20. Fluid under pressure also will flow from the ahead controlpipe lil into the chamber Il in the cam shift cylinder device 5, through one or the other of the pipes 333 or 334, through the inverse doublecheck valve device l0l and the pipe 32l-to the control chamber in the relay Valve device 4fl0* Which willrespond to disestablish its communication H3 and to establish its communication H9. The chamber 15! in the interlock device8 "then becomes connected to thenow vented chamber l3'l therein by way of the pipe '305', communication l l9 in relay valve device 400 and thepipe- 305. The piston [54 and shoe l6l' in device 8 will-both remain in theirrepos'epositori at-this time as starting means is brought into operation to turn the engine over in its ahead direction in acwill be.

' cord with position of the operators control lever In response to -movement of the operators control lever back to its Stop position in which both the ahead and astern control pipes [9, 23 become vented, the parts of the apparatus of Figs. 1, 2 will assume their respeceive positions aspreviously described as the engine comes to a stop.

'Nowassume thatwith the engine stopped, after previousoperation in its ahead direction, it is desired. to start the engine operating in its astern direction through movement of the operators lever 44 out of Stop position to a position on the Astern side of Stop position, thereby eiecting supply of fluid under pressure to the astern controlpipe 20 while maintaining the ahead control pipe |9 vented.

Fluid under pressure from the astern control pipe 26 will flow by way of the double check valvedevice ll) and the pipe 300 to the control chamber in the relay valve device 9 to cause same to establish its communication IIS connectingthe pipes 33l and 392 to allow fluid under pressure from the astern control pipe to flow by way of the unseated valve 32' and chamber 137 in the directional interlock device 8 to the chamber 32 in the fuel cut-off cyclinder device 6 to hold -fuel supply cut-oi to the engine.

At' the same time, fluid under pressure from the astern control pipe 2flwill flow into the chamber 18 in the cam shift cylinder device 5 whose chamber H will be vented va the ahead control pipe 19 at the time to cause movement of the cam shift piston I 6 from its -Ahead posi tion, in which it is shown in the drawing, to its opposite Astern position to condition the engine for operation astern.

-Just prior to movement of the cam shift piston l6 out of its Ahead position, both pipes 333 and 334 will be vented to atmosphere by way of chamber ll, then initialmovement of said piston out of its Ahead position toward its Astern position will uncover the pipe 334 to the pressurized chamber IB while the pipe 333 remains vented va chamber I'l, and finally upon attaining its Astern position will uncover the pipe333to thepressurized chamber l8, so that both pipes 333, 334 then become charged with fluid under pressure.

It will be appreciated from previous description that at the time fluid under pressure is supplied to the chamber 18 in the cam shift cylinder device 5 with the chamber ll vented to atmosphere to cause the piston 16 to move from its Ahead position to its Astern position, the

pipe 32l, hence the control chamber 202 in the relay valve device 400, will remain vented to atmosphere by way of the inverse double check :valve device 401 until both pipes 333, 334 become charged withfluid under pressure upon attainr ment of the cam shift piston 16 in its Astern position.

v Itwill be seen thatduring the time that the above shifting in position is occurring, with control chamber 202 in relay valve device 400 vented to atmosphere, its communication I l9 will reach the pressure chamber 151 by way of the pipe 305, and said pressure chamber l5l will remain vented by way of the pipe 305, said communication I 13 in device 489 and the pipe35.

At the time that the cam shift piston attains its new Astern position and the control chamber 202 in the relay valve device 400 becomes charged as aforedescribed with fluid under pressure, said relay valve device will disestablish its communication H8 which connects the pipe 305 to atmosphere and will establish its communication IIS which connects the pipe 305 to the charged pipe 305. Fluid under pressure will then flow from the pipe 305 va the communication H in the device 400 and the pipe 305 to the pressure chamber l51 in the directional interlock device 8 to move the piston l54 to cause engagement of the shoe l6l with the engine crank shaft l.

Also upon completion of shift of the cam shaft 2 by movement of the cam shift piston l6 to its Astern position, the starting means (not shown) will be brought into operation to turn the engine over in its new or astern direction. Upon initial turning movement of the shaft l in its new or astern direction, through resultant shift in position of the shoe ISI in engagement therewith, the valve l3l will be unseated and the valve l32 seated, whereupon fluid under pressure will release from the pressure chamber 151 in device 8 by way of the pipe 305, communication IIS in relay valve device 400, the pipe 305, said chamber 31, the unseated valve l3l, chamber [33 and the vented ahead control pipe l9 to allow the shoe I6l to be retracted by the spring I'I0 to its repose position disposed away from the shaft I in accord with a feature of the invention. The pin [66 will then project into the notch IB! to lock the link l52, cams l4, IS and valves I3l and I32 in their respective positions last assumed.

Upon venting, as above described, of the chamber l3'l in the directional interlock device 8, fluid under pressure will release from the chamber 32 in the fuel cut-off cylinder device 6 by way of the pipe 30l, communication II9 in the relay valve device 9, the pipe 302 and said chamber 31 to release said fuel cut-off cylinder device to allow the fuel control shaft 3 to be moved for effecting supply of fuel to the engine for running same in its astern direction.

It will be appreciated that each time a reversal in the direction of operation of the engine is called for by establishment of pressure in one of the control pipes l9, 20 while venting th other of said pipes to atmosphere, as in a snap or flash reversal while the engine is operating, the inverse double check valve device 401 in conjunction with cylinder device will s0 control operation of the relay valve device 400 as to prevent supply of fiuid under pressure from the chamber l31 in interlock device 8 from reaching the pressure chamber I5'I in said device 8 until the cam shift piston IB has moved from its one position to its opposite position to condition the engine for operation in the direction opposite to that in which it is running. According to a feature of the invention, by means of such an arrangement, operation of the piston [54 in the interlock device 8 is thus delayed to allow the shaft l to slow down while turning in its original direction with fuel supply cut-oi to the engine before the shoe l6l is moved into engagement with said shaft l, thereby reducing the amount of wear on said shoe over that wear which said shoe otherwise would sustain if moved into engagement with said shaft earlier at higher speed.

All other parts of the apparatus will function as described previously in relation to Fig. 1.

18 DESCRIPTIONFIG. 3

According to the structure shown in Fig., 3, I provide a relay valve device 500, which, for sake of illustration, may be alike schematically to the relay valve device shown in detailed section in Fig. 5. The relay valve device 500 in Fg. 3 is adapted to be incorporated in the apparatus shown in Fg. 1 to delay supply of fiuid under pressure to the pressure chamber l51 in the directional interlock device 8 and to effect quick release of such fluid under pressure from said pressure chamber.

According to this feature of the invention, in the relay valve device 500, its control chamber 202 is connected to the pipe 305 and thereby to the chamber I3'I in the directional interlock device 8, its chamber 204 is connected to atmosphere by way of such as a pipe 50l, its chamber 205 is connected to the pipe 305 and thereby to the pressure chamber l51 in said directional interlock device, and its chamber 206 is connected to a source of supply of fluid under pressure such as the control supply pipe 40.

In operation of the apparatus shownin Fig. 1 and embodying the relay valve device 500 of Fig. 3 as above described, when fluid under pressure is supplied to the chamber I3'I in the directional interlock device 8, as will be effected when a reversal in direction of operation of the engine is called for, such fiuid under pressure will flow from said chamber l3l via the pipe 305 to the control chamber in the relay valve device 500 which relay valve device will then respond, substantially upon attaimnent of full control line pressure, to disestablish its communication H8, which at the time Will be connecting the.pipe 305 and hence the chamber l5'l in the directional interlock device 8 to atmosphere via pipe 50l, and to establish its communication H9 which connects the pipe 305 to the supply pipe 40. Fluid under pressure will then flow from the supply pipe 40, through the communication H9 in the relay valve device 500, and the pipe 305 to the pressure chamber l5l in the directional interlock device 8 to actuate the piston 54 to cause engagement of the shoe l6l with the engine crank shaft l. As soon as the direction of rotation of the crank shaft l is in accord with position of the operators control lever 44, the valves l3l and [32 will be caused to assume positions, as aforedescribed herein, to effect disconnection between the chamber l3'l and whichever of the control pipes I9, 20 is charged at the time and connection of said chamber 131 to the other vented control pipe. Fluid under pressure will then release from the control chamber in the relay valve device 500 to cause same to disestablish its communication H9 connecting the pipe 305 to the supply pipe 40 and to establish its communication H8 Which vents said pipe 305 to atmosphere by way of the pipe 50l. Fluid under pressure will then release from the chamber l51 in the directional interlock device 8 directly by way of the pipe 305 and the relay valve device 500 to allow for rapid retraction of the shoe ISI to its repose position disposed away from the shaft I. It will be seen that the shoe automatically is retracted upon turning of the engine crank shaft I in its proper direction in accord With position of the operators control lever 44 and that such retraction may be prompt by virtue of a local release of fiuid under pressure from the chamber 151 by way of the relay valve device 500 which may be mounted on or adjacent to the directional interlock device.

19 It should be pointed .out that through exchange in the relay valve device 500 of control springs 215 of difierent spring values, the time at-whichthe relay valvedevioe50t will=trip to -eiectoperation ofshoe [Si subsequent to initial movement of the operators lover :i-s to a new positionmay be changed as desired, a heavy controlspring2i5 affording a delay until the pressure --of fluid supplied to the control chamber from-one-or the other of the control pipas IS, 20 builds up substantially to its maximum value. -By means of the relay valve device5t0, therefore,-adelay in operation of the directional interlock shoe IBI similar to the delay afforded by employment of the structure shown in Fig. 2

maybe provided to save shoe wear. At the same time,-a heavy control spring 2 l 6 in the relay valve device 500 will allow for rapid release of the directionaj interlock shoe IBI away from the sha;ft I since only a slight reduction in pressure of fiuid in the control chamber will open the pressure chamber l 51 in device 8 to atmosphere directly by way of said relay valve device rather than by wayof the chamber 13l,chamber l33.or 34, control pipe l9or 2, and the operators control device 1 as in operation of the apparatus as shown in Fig. 1 without the employment of the relay valve device in-Fig. 3.

SUMMARY It will be seen that I have provided engine-control :apparatus employing a direction sensing interlock.device which will substantially minimize :wear.on.the friction shoe of such deviceby limiting the time that said shoe is held in engagement and :movable by engagement with said member,

and fluid pressure means operable in response to supply of fluid under pressure to said delivery chamber to effect movement of said direction sensing means into engagement with said motion reversible member.

2. :In combination, a motion reversible member, :two control pipes, a delivery chamber, control means for eiecting supply of fluid under pressure to either of said control pipes selectively While venting the other of said control pipes, valve means movable to one position or to another position to either establish connection between said delivery chamber and a particular one of said control pipes Or between said delivery chamber and the other of said control pipes, direction sensing means movable by engagement with said motion reversible member in one direction or a reverse direction to eiect movement of said valve means to said one position or to said other position, respectlvely, and iluid pressure means responsive to supply and release of fluid under pressure to and from said delivery chamber to efiect movement of said direction sensing means into and out of engagement with said motion reversible member, respectively.

3. In combination, a :reversible engine -crank shaft rrotatable in anahead direction or in :an .astern:direction, an ahead control pipe, an .astern controlpipe, a delivery chamber, control means operable to an ahead position to eiTect.supply-of fluid under pressure :to said ahead control pipe while ventingsaid astern control pipe and to:said estem position to eiect supply of fiuid under pressure to. said astern control pipe while venting said ahead.oontrol pipe, valve means movable to one position or to another position to establish connection between said delivery chamber and said astern control pipe or said ahead control pipe, respectively, direction sensing means rmovable by engagement with said. shaft'when'rotating :in theahead direction to eiectmovement of said valve mean to said one position and when zrotating in the astern directionto efiect movement of said valve means to said other position, and piston means responsive to supply and ;releaseof fluid under pressure to and from said delivery chamber to effect movement of said direction 'sensing mean into and out of engagement*with said shaft, respectively.

4. .In combination, a reversible engine xcrank shaft .rotatable in an ahead direction or in .an astern direction, an ahead :control pipe, an.astern control pipe, a delivery chamber, control means operable to an ahead position to efiect.supply.of fiuid under pressure to said ahead control pipe while ventingrsad.astern control pipe and to said astern position to efiect supply of fluid under pressureto.said astern control pipewhile venting said aheadcontrol .pipe, valve means movable to one position or to another position to establish connection between said delivery chamber and said zastern control pipe or said ahead control pipe, respectively, direction sensing means movable by engagement with said shaft when rotatzing :in the ahead direction to efiect:movement :of said valve means )O one position and when.rotating .in the.astem dire:ctionzto eiect movement of said valve means to said other position, piston means regponsive to supply and release of fluid under pressure to andirom said-delivery dhambar to eiect movement of said direction .sensing means into and out of engagement with said shaft, respectivcly, and engine fuel cutofi means operable in response to supply of fiuid under;pressure to said delivery-chamber.

5. ln:ccmoinationwith a source of fluid under pressure and :a reversible engine crank shatrotatable in an ahead direction or astern direction, :a-n ahead control pipe, an astern control pipe, a delivery chamber, an operators control device -comprising an operators lever movable to an ahead position to effect supply of fiuid under pressure from said. source to said ahead control pipe and venting of said astern control pipe, to -a stop position to efiect venting of both the ahead and astern control pipes and to an astern position to effect supply of luid under pressure from said source to said astern control pipe and ventng of said ahead control pipe, valve means movable.to one position to connect said delivery chamber to said ahead control pipe or to another position to connect said deliver chamber to said astern control pipe, direction sensing means movable by engagement with said shaft to eiect movement of said valve means to said one position or to said other position according as to whether said shaft is rotating in its ahead or in its atsern direction, respectively, piston means responsive to supply and release of fluid under pressure to and from said delivery chamber to effect movement of said direction sensing means into and out of engagement with said shaft, fuel cut-oi means responsive to supply of fluid under pressure to a pressure chamber to eiect termination of supply of fuel to the engine, relay valve means responsive to supply of fluid under pressure to a control chamber to establish a first communication to contact said pressure chamber to said delivery chamber and to release of fluid under pressure from said control chamber to disestablish said first communication and establish an alternate communication to connect said pressure chamber to said source of fluid under pressure, and a double check valve device havin two inlet openings connected to the ahead and astern control pipes, respectively, and an outlet opening connected to said control chamber.

6. In combination, a motion reversible member, two control pipes, a delivery chamber, control means for effecting supply and release of fluid under pressure to and from either of said two control pipes selectively, valve means conditionable according to direction of motion of said member to selectively establish connection between said delivery chamber and one or the other of said control pipes, direction sensing means operatively connected to said valve means and movable by engagement with said member, fluid pres sure means operable in response to supply of fluid under pressure to said delivery chamber to eiect movement of said direction sensing means into engagement with said motion reversible member, and timing means to delay said response.

7. In combination, a reversible engine crank shaft, two control pipes, a delivery chamber, control means for efiecting supply and release of fluid under pressure to and from either of said two control pipes selectively, engine reversing means movable to assume one position or another position in response to selective supply of fluid under pressure to said control pipes, respectively, valve means conditionable according to direction of motion of said shaft to selectively establish connection between said delivery chamber and one or the other of said control pipes, direction sensing means operatively connected to said valve means and movable by engagement with said shaft, fluid pressure piston means operable in response to supply of fluid under pressure to said delivery chamber to move said direction sensing means into engagement with said shaft, and timing means including inverse double check valve means and relay valve means to prevent response of said piston means during movement of said engine reversing means,

8, In combination, a reversible engine crank shaft rotatable in ahead or astern directions, an ahead control pipe, an astern contro1 pipe, a delivery chamber, engine reversing control means having ahead and astern positions for effecting supply of fluid under pressure selectively to said ahead control pipe and to said astern control pipe, respectively, friction means movable in one direction or an opposite direction by engagement with said shaft when rotating ahead or astern, respectively, valve means conditioned by said friction means when moved in said one direction or said opposite direction to selectively connect said delivery chamber to said astern control pipe or to said ahead control pipe, respectively, fluid pressure piston means responsive to supply of fluid under pressure to a pressure chamber to move said friction means into engagement with said shaft and upon release of fluid under pressure from said pressure chamber to retract said irction means away from said shaft, and relay valve means responsive to supply of fluid under pressure to said delivery chamber to supply fluid under pressure -to said pressure chamber and responsive to release of fluid under pressure from said delivery chamber to release fluid under pressure from said pressure chamber.

9. In combination with a source of fluid under pressure, a friction shoe adapted for frictional engagement with a reversible rotatable shaft to be moved tangentially by such engagement in one or an opposite direction according to direction of shaft rotation, a pressure chamber, piston and return spring means operatively connected to said friction shoe responsive to pressure of fluid supplied to said pressure chamber to advance said shoe in a shaftwise direction and responsive to dissipation of such pressure in said pressure chamber to retract said shoe in a counter-shaft- Wise direction, one control chamber, another control chamber, a delivery chamber, valve means operably connected to said shoe adapted to selectively establish a fluid pressure communication between said one or said other control chamber and said delivery chamber according to tangential movement of said shoe in its one or opposite direction, respectively, a fluid pressure conduit connecting said pressure chamber to said delivery chamber, one control pipe and another control pipe connected to said one control chamber and said other control chamber, respectively, and an operators control valve device having an operators handle movable in a direction corresponding to tangential movement of said shoe in its said one direction to establish connection between said source and said other control pipe and between the atmosphere and said one control pipe and movable in a direction corresponding to tangential movement of said shoe in its said other direction to establish connection between said source and said one control pipe and between atmosphere and said other control pipe.

10. The combination as set forth in claim 9 including a positioning piston pressure chamber, a positioning device comprising positioning piston and return spring means responsive to pressure of fluid supplied to said positionng piston pressure chamber to assume one position and responsive to dissipation of such pressure in said piston pressure chamber to assume another position, a control chamber, relay valve means responsive to supply and release of fluid under pressure to and from said control chamber to selec tively establish fluid pressure communication between said piston pressure chamber and either said delivery chamber or said source, respectively, and double check valve means responsive to establish connection between said control chamber and whichever of the one and other control pipes is charged with fluid under pressure.

ll. The combination as set forth in claim 9, including a control chamber relay valve means interposed in said fluid pressure conduit respons1ve to supply and release of fluid under pressure to and from said control chamber to selectively establish fluid pressure communication between said pressure chamber and either said delivery chamber or atmosphere, respectively, a cam shift cylinder comprising a -reciprocable piston dividing the interior of said cylinder into two pressure chambers connected to the two control pipes, respectively, said cylinder having two spacecl apart ports opening to the inner cylinder surface on which said piston slides, said ports being disposed so that both open to one or the other side of said piston when same attains one or the other of two opposite extremepositions, respectively, and an inverse double check valve device having opposite inlets connected to said ports,

respectively, and an outlet connected to said control chamber, operabie to supply fiuid under pressure to said control chamber only when both inlets are pressurized and to vent said control and release of fluid under pressure to and from said control chamber to selectively establish communication between said pressure chamber and said seurce or atmosphere, respectively.

RALPH T. W HITNEY.

REFERENCES CITED The following references are of record in the -file of this patent:

UNITED STATES PATENTS Number Name Date 2,395,202 Stevens et al Feb. 16, 1946 2,413,390 Stevens Dec. 31, 1946 2,444,273 Stevens June 29, 1948 

